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Hi Guys,

I'm starting with RMI (I actually started programming in Java a month ago)
and I have some questions/doubts:

1.- Why I don't get any persistent connections? All connections initiated
from Clients to Server are in a status of TIME_WAIT as soon as there is no
more interactivity (Remote method invocations) between them. Does this mean
that every time I invoke a remote method, RMI creates a socket connection??
Is there a way to make a permanent connection?

2.- If I register a remote client object reference (a callback) to the
server, and the pass this remote reference to another client (ie Client A
registers to Server, the Server gives Client B the ref of A), what will
happen? A and B will establish a TCP connection directly?

Well, Any ideas are welcome!!

Thanks!

Agustin.

Hi Joe,

Thanks a lot for the quick reply! One more thing: Is it safe to use the
sun.rmi.transport setting? Since I read the Warning sign... about
standards.. bla bla...

Anyway, thanks a lot!

Agustin.

"Joseph Dane" <> wrote in message
news:...
> "Agustin Chernitsky" <> writes:
>
> > 1.- Why I don't get any persistent connections? All connections
initiated
> > from Clients to Server are in a status of TIME_WAIT as soon as there is
no
> > more interactivity (Remote method invocations) between them. Does this
mean
> > that every time I invoke a remote method, RMI creates a socket
connection??
> > Is there a way to make a permanent connection?
>
> connections are persistent, to a point. the default interval after
> which the connection is closed is pretty short (15 seconds) and can
> be changed by setting the property sun.rmi.transport.connectionTimeout
>
> see this page for descriptions of the sun.rmi properties you can set:
>
> http://java.sun.com/j2se/1.4.2/docs/...roperties.html
>
> > 2.- If I register a remote client object reference (a callback) to the
> > server, and the pass this remote reference to another client (ie Client
A
> > registers to Server, the Server gives Client B the ref of A), what will
> > happen? A and B will establish a TCP connection directly?
>
> yes. the address and port number on Client A are encoded in the stub
> passed to the server.
>
> --
>
> joe

"Agustin Chernitsky" <> writes:

> Thanks a lot for the quick reply! One more thing: Is it safe to use the
> sun.rmi.transport setting? Since I read the Warning sign... about
> standards.. bla bla...

it's safe, but you'll have to be a little careful. Sun chose to
publicly document the settings, which is something they don't
typically do with internal, non-public APIs, because a lot of people
use their RMI implementation and need to tweak these parameters.

that said, they put that disclaimer up for a reason. if Sun decides
to change their implementation, those properties could change, and
they'd be under no obligation to tell you. I'd say that the
likelyhood of this is low, though, and anyhow if you stick with a
single version of Java you'll be safe.

--

joe